From patchwork Thu Apr 15 16:42:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Don Brace X-Patchwork-Id: 12205763 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 87ACFC433B4 for ; Thu, 15 Apr 2021 16:42:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A6F561165 for ; Thu, 15 Apr 2021 16:42:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233343AbhDOQm3 (ORCPT ); Thu, 15 Apr 2021 12:42:29 -0400 Received: from esa.microchip.iphmx.com ([68.232.153.233]:35164 "EHLO esa.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232752AbhDOQm2 (ORCPT ); Thu, 15 Apr 2021 12:42:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1618504925; x=1650040925; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=OMUkNAfY7ePatloNoEPpTvAlKh5zC5EAXg/FPXrh/Sg=; b=M0+CZktzeev9LuwkwsVKGSnI3qShH1rVvPTZUJ673PCO99lQ90R/8mYv FhHjEC1M8b0IYMxQXhRJDPa3MN08uRcnferykRQVY18OG0mRIbE9eB3NE yeHtmLdSQao4a3C6HOp6iDgmM/02AdbpvvrNUGWlh6si0P6wYyZD4lpWV 85mJv0msf7TP8qbCr3IT6FBgnVbVNcPcqF04sKwxVvrfu36Hd4yZ7o01n 9whAWWsPYRRgHxMuvkTwNtvcOyHoduFn48aYCS1Ep1oKUAXukbLdWKm4P 4QP5v1kxImXzGpptjQc2FysMGzcpdbP10KnhFRPf2uTIX2ACf6enARPDk A==; IronPort-SDR: UNk3md10ZHpBl04lUHQj0KgzWuipyaqRvtIWwLj0Nap3JkqCRYAHN44Alj2lG4wcsPwgQBG1m1 VYVQtGfcAQtDnPbWJYqdcURLmdSMdfiNdJ8s5dCu7ETHxk3F8hWNQN8w9WzT3fZE17YhTXScWl HIfNEw5MdONUWZAvrZ4Gdfn61NHDBHqE1BMajOP6gHLi8achwIO0GT2hUgK1pMbm2mOdJNEqgG EXmF/qmdfLRvkeILpFgbMklOZALIHSzAEmurQBR15xIetBlvS+ZbmJ/J4GI9Lfnfqsz2CtacUW fbg= X-IronPort-AV: E=Sophos;i="5.82,225,1613458800"; d="scan'208";a="117169982" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa3.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 15 Apr 2021 09:42:05 -0700 Received: from chn-vm-ex01.mchp-main.com (10.10.85.143) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 15 Apr 2021 09:42:05 -0700 Received: from [127.0.1.1] (10.10.115.15) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server id 15.1.2176.2 via Frontend Transport; Thu, 15 Apr 2021 09:42:04 -0700 Subject: [PATCH 1/2] smartpqi: fix blocks_per_row static checker issue From: Don Brace To: , , , , , , , , , , , CC: Date: Thu, 15 Apr 2021 11:42:04 -0500 Message-ID: <161850492435.7302.392780350442938047.stgit@brunhilda> In-Reply-To: <161850488487.7302.7018870513204678832.stgit@brunhilda> References: <161850488487.7302.7018870513204678832.stgit@brunhilda> User-Agent: StGit/0.23-dirty MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Dan Carpenter found a possible divide by 0 issue in the smartpqi driver in functions pci_get_aio_common_raid_map_values and pqi_calc_aio_r5_or_r6. The variable rmd->blocks_per_row is used as a divisor and could be 0. Link: https://lore.kernel.org/linux-scsi/YG%2F5kWHHAr7w5dU5@mwanda/ Fixes: 6702d2c40f31 ("scsi: smartpqi: Add support for RAID5 and RAID6 writes") Using rmd->blocks_per_row as a divisor without checking it for 0 first. Correct these possible divide by 0 conditions by insuring that rmd->blocks_per_row is not zero before usage. The check for non-0 was too late to prevent a divide by 0 condition. Add in a comment to explain why the check for non-zero is necessary. If the member is 0, return PQI_RAID_BYPASS_INELIGIBLE before any division is performed. Reported-by: Dan Carpenter Reported-by: kernel test robot Reviewed-by: Scott Benesh Reviewed-by: Scott Teel Reviewed-by: Mike McGowen Reviewed-by: Kevin Barnett Signed-off-by: Don Brace --- drivers/scsi/smartpqi/smartpqi_init.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c index 3b0f281daa2b..797ac699b7ff 100644 --- a/drivers/scsi/smartpqi/smartpqi_init.c +++ b/drivers/scsi/smartpqi/smartpqi_init.c @@ -2510,6 +2510,8 @@ static int pci_get_aio_common_raid_map_values(struct pqi_ctrl_info *ctrl_info, /* Calculate stripe information for the request. */ rmd->blocks_per_row = rmd->data_disks_per_row * rmd->strip_size; + if (rmd->blocks_per_row == 0) /* Used as a divisor in many calculations */ + return PQI_RAID_BYPASS_INELIGIBLE; #if BITS_PER_LONG == 32 tmpdiv = rmd->first_block; do_div(tmpdiv, rmd->blocks_per_row); @@ -2559,6 +2561,10 @@ static int pqi_calc_aio_r5_or_r6(struct pqi_scsi_dev_raid_map_data *rmd, #if BITS_PER_LONG == 32 u64 tmpdiv; #endif + + if (rmd->blocks_per_row == 0) /* Used as a divisor in many calculations */ + return PQI_RAID_BYPASS_INELIGIBLE; + /* RAID 50/60 */ /* Verify first and last block are in same RAID group. */ rmd->stripesize = rmd->blocks_per_row * rmd->layout_map_count; @@ -2662,8 +2668,6 @@ static int pqi_calc_aio_r5_or_r6(struct pqi_scsi_dev_raid_map_data *rmd, rmd->q_parity_it_nexus = raid_map->disk_data[index + 1].aio_handle; rmd->xor_mult = raid_map->disk_data[rmd->map_index].xor_mult[1]; } - if (rmd->blocks_per_row == 0) - return PQI_RAID_BYPASS_INELIGIBLE; #if BITS_PER_LONG == 32 tmpdiv = rmd->first_block; do_div(tmpdiv, rmd->blocks_per_row);